As far as I know this is the only subway in Oakville that's open 24 hours and that alone is worth 5 stars. I rarely have the desire or intent to eat a sub before 1am so this place has been a life saver on a couple occasions.
Unfortunately the downside to any subway (at least the ones in Oakville) is that they're always severely understaffed so even if there are only a couple people in front of you, be prepared to wait because there will likely only be one employee working and English is likely their second language so be patient.